walk she took to her colorado grade school every morning. But last friday, 10-year-old jessica ridgeway never made it to her fifth grade classroom. The only clue, her school bag found six miles away. As police search door-to-door, in a town under the microscope. Her family speaks out for the first time. And abc's clayton sandell has the latest from colorado. Reporter: This is 10-year-old jessica ridgeway, horsing around a few months ago with a home video camera and the family dog. That's the camera. See? Reporter: Tonight, the video has a special urgency. It was released by colorado police because jessica is missing. And today, for the first time, her parents are speaking out. It's the worst thing I've ever been through. Reporter: The fifth grader vanished last friday, while walking the short distance between her home and her You don't hear anything. And then, you get the pit in your stomach that you don't want any parent -- any parent to ever experience in their whole entire life. Reporter: Late this afternoon, the fbi searched jessica's home, removing boxes headed for an evidence lab. Sources tell "nightline" the family consented to the search. Jessica's parents, never married, have been to court recently with custody issues. But police say those issues are unrelated to her disappearance. I just want to find my daughter. Reporter: It was early friday morning that jessica was last seen by her mother, as she left for school. I watched her walk out the door. And she shut the door. And that's the last time I saw her. Reporter: Jessica never arrived to school friday morning. But the staff called her mother to report her absence. But she told police she was sleeping after working graveyard shift after a tech company and didn't hear the call. By the time she got the voicemail message, eight, critical hours had passed. The idea she could be eight hours in another direction, put the police way behind in figuring out where this child might be. Reporter: By saturday, more than 800 volunteers turned out to help find jessica, scouring fields and hillsides. They gave us descriptions of what the little girl was wearing the that's what we're trying to find. Reporter: Police brought in teams of scent-tracking dogs to search the family's neighborhood. They looked in everything. Washers, dryers. You find this girl, that's the main concern. Reporter: They found nothing. But sunday, that first real clue. A man called police about a backpack and water bottle with jessica's name on it, found on the sidewalk about six miles from where she was last seen. We've been looking for a lead. This possible is that. Reporter: Police swarmed the their cars. We believe the backpack to be jessicas. A vast majority. Up to 90% of child abductions, are by parents or individuals close to the child. Reporter: So far, jessica's parents are said to be cooperating with police. Her father, jeremiah bryant, is on felony probation in missouri, for second-degree domestic assault. I'm going to give you a flyer. Reporter: But tonight, investigators say they have no suspects. And are relying on the public for leads. Everybody who knows me and knows her and knows our family, knows we didn't do anything. Reporter: With time, crucial in a case like this, parents in the community are wondering, should the school have called more than once to flag jessica's absence? We make the phone call to the number that the parent requests we call. Reporter: According to jessica's mom, that voicemail wasn't received for eight, long hours. Why not make a second call? Those are the questions that we will be talking about. And we will be asking ourselves. I need her to walk back through that door. Reporter: Jessica's backpack is being examined for dna evidence. Until more clues are unearthed, this mystery will continue to rattle residents, who are praying, tonight, for a little girl's safe return. I'm clayton sandell, for "nightline," in westminster, colorado.

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